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balabala

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\bibitem [{Note1()}]{Note1}
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  \bibinfo {note} {Because the gradient depends on the commutator with $\protect \mathaccentV {hat}05E{H}$         such that measurements associated with terms in         $\protect \mathaccentV {hat}05E{H}$         which commute with a specific operator in the pool can be skipped, the actual number of measurements needed is difficult to predict, as it will depend on the operator pool chosen. Getting estimates for this number for various pools will be the focus of future work.}
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\bibitem [{\citenamefont {{Huggins}} \   et~al. (2019)\citenamefont
  {{Huggins}}, \citenamefont {{McClean}}, \citenamefont {{Rubin}},
  \citenamefont {{Jiang}}, \citenamefont {{Wiebe}}, \citenamefont {{Whaley}},\
  and \  \citenamefont {{Babbush}}}]{190713117Efficient}
  \BibitemOpen
  \bibfield  {author} {\bibinfo {author} {\bibfnamefont {W.~J.} \  \bibnamefont
  {{Huggins}}}, \bibinfo {author} {\bibfnamefont {J.}~\bibnamefont
  {{McClean}}}, \bibinfo {author} {\bibfnamefont {N.}~\bibnamefont {{Rubin}}},
  \bibinfo {author} {\bibfnamefont {Z.}~\bibnamefont {{Jiang}}}, \bibinfo
  {author} {\bibfnamefont {N.}~\bibnamefont {{Wiebe}}}, \bibinfo {author}
  {\bibfnamefont {K.~B.} \  \bibnamefont {{Whaley}}},  \  and \  \bibinfo {author}
  {\bibfnamefont {R.}~\bibnamefont {{Babbush}}}, \  }\href
  {https://arxiv.org/abs/1907.13117} {\bibfield  {journal} {\bibinfo  {journal}
  {arXiv e-prints} \  } (\bibinfo {year} {2019})}\BibitemShut {NoStop}
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